Road Scholar Science Olympiad

Two wires carrying electricity can create a spark if they come too close together. This spark can start a fire. Wires carrying electricity are usually covered with plastic to keep them from starting a fire. Why does the plastic keep the electricity from starting a fire?

• Plastic is a good insulator.

• Plastic is softer than wire.

• Plastic can melt when heated.

• Plastic conducts electricity.

A teacher gives a student four clear sealed containers. Each container holds a different substance. The student records some observations about the substance in each container.

Container 1: The substance takes the shape of the container and is clear. Small particles float on top of the substance.
Container 2: The substance is hard and cube-shaped. The surface of the substance is shiny.
Container 3: The substance is not visible, and the container appears empty.
Container 4: The substance is cold and made of crystals.

Based on these observations, which container most likely holds only gas?

• Container 1

• Container 2

• Container 3

• Container 4

Which of these is the best conductor of electricity?

• Glass rod

• Cotton string

• Plastic tubing

• Copper penny

A teacher mixes a white powder into a beaker of water. The powder cannot be seen in the water. The teacher then heats the mixture until the water evaporates and the powder can be seen again. Which property of the powder is the teacher demonstrating?

• Solubility

• Density

• Conductivity

• Mass

Tags

NGSS.MS-PS1-4

A student measures the temperature of water being heated on a hot plate. The student observes that the temperature of the water is 53°C. How many more degrees Celsius must the temperature rise before it reaches the boiling temperature of water?

• 159°C

• 69°C

• 20°C

• 47°C

Tags

NGSS.MS-PS1-4

A student observed liquid wax dripping down the side of a burning candle. After putting out the candle's flame, the student left the room. Several hours later the student observed that there was no longer any liquid on the side of the candle. Which statement explains what most likely happened to the liquid wax?

• The heat given off by the flame caused the candel wax to evaporate.

• The liquid wax changed back into a solid as it cooled.

• The liquid wax condensed and was absorbed by the candle.

• None of the above

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

A student adds 10 grams of four different powdered solids into four different beakers. The student then adds 100mL of water to each beaker, stirs the mixtures, and allows them to sit for half an hour before recording observations. Which question is the student most likely trying to answer with this investigation?

• At what water temperature do the substances dissolve?

• How much water is needed to cause a substance to change state?

• What causes a substance to sink when put in water?

• Which substances dissolve in water?

A student fills two identical beakers with the same volume of water. The student places on beaker in the freezer and the other beaker on a hot plate. After 5 minutes the student observes that the temperature of the water in the freezer is 19°C and the temperature of the water on the hot plate is 42°C. Which statement best describes the relationship between the two beakers of water and the freezing and boiling point of water?

• The temperature of the water on the hot plate must increase 58°C before it boils, and the temperature of the water in the freezer must decrease 32°C before it freezes.

• The temperature of the water on the hot plate is closer to the boiling point than the temperature of the water in the freezer is to the freezing point.

• The temperature of the water in the freezer must decrease by 19°C before it freezes, and the temperature of the water on the hot plate must increase 170°C before it boils.

• The temperature of the water in the freezer is closer to the freezing point than the temperature of the water on the hot plate is to the boiling point.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Which property of light causes the bending of pencil in water?

• Reflection

• Refraction

• Dispersion

• Scattering

The color of a mineral's powder is called ____________.